Step 1: Supplies.
Clear frosted tubing; it also comes in matte black.
For the bracelet I'm using memory wire; for the necklace I'm using beading wire (the picture shows black, but I changed to silver as it looks nicer in the clear tubing). A colored wire would also look cool through the translucent tubing.
Step 2: Rubber Tubing
Feeding the tubing onto the memory wire bracelet.
While my beads had holes large enough to go over the tubing, they would slide around. If you only want them at the center of a necklace, that would be fine, but I wanted them spread out evenly, so I then cut the tubing into sections. It kind of gives the illusion that the tubing goes through the beads; this would also work great on beads where the holes are too small for the tubing.
Step 3: Alternating Beads and Tubing.
I fed the pendant and spacer beads onto the beading wire, then the tubing sections.
Step 4: Bracelet, Finished
Finished bracelet; in the second picture I added shell dangles to the loops I made on the ends of the wire. Memory wire is tough to bend but you can do it.
You could add crystal dangles, charms, etc.
Step 5: Finishing the Necklace
Once your necklace is long enough, thread some crimp beads (I like two for security, and I like to put a spacer bead after them to keep the wire from stressing), add a clasp, and crimp. You can use special crimping pliers or just regular needlenose pliers; the crimping ones make a smaller bead-like result while regular pliers will mash the crimp flat into a rectangle.